In a process of manufacturing a semiconductor device, a step of irradiating a substrate with ultraviolet rays to perform a desired process (e.g. a peripheral exposure for exposing a periphery of a substrate to light) on the substrate has been used. Various new methods have also been proposed for techniques of forming a pattern on a substrate. Among the series of methods, a new technique using ultraviolet rays has been proposed. For example, these methods include a process of irradiating the entire surface of a resist film on a substrate with ultraviolet rays, thereby modifying the resist film, a method of irradiating a block polymer composed of two kinds of polymers with ultraviolet rays and subsequently developing the block polymer, thereby forming a line pattern, and the like.
Considering a need for simplification of the configuration of an apparatus when substrate processing is performed using ultraviolet rays as described above, incorporation of air is not avoidable even when an inert gas atmosphere is used as a processing atmosphere, and thus ozone is generated. For this reason, there is a concern that the generated ozone may be problematic. Conventionally, an example of effective configurations of processing apparatuses using ultraviolet rays includes a configuration for mounting a substrate on a mounting table and passing the mounting table below an ultraviolet ray irradiation unit. However, there is a concern that a drive system for the mounting table may be corroded by ozone.
In consideration of this, in a substrate processing apparatus using ultraviolet rays, it is required to suppress corrosion of a drive system caused by ozone, while inhibiting particles from the drive system from adhering to a substrate. It is also required to suppress the incorporation of air when an inert gas atmosphere is used as the processing atmosphere.